Disclosed is a space cold gas thruster operating with a solid propellant. The cold gas thruster includes a tank suitable for containing a solid propellant and a tank heating device suitable for sublimating the solid propellant and forming gaseous propellant, the tank having an aperture for transferring the gaseous propellant outside the tank, such as a nozzle. Also disclosed is a process for determining the amount of remaining propellant in the propellant tank of the disclosed cold gas thruster.

The present invention provides an automatic chemical analysis apparatus and an electrical impedance spectrometry device which make it possible to detect the state of a stirring mechanism prior to performing a stirring operation. The automatic chemical analysis apparatus dispenses a reagent and a sample to be analyzed into a reactor vessel 107, and performs stirring by applying sonic waves to the reactor vessel 107. The automatic chemical analysis apparatus comprises: a piezoelectric element 201 that generates sonic waves; a plurality of split electrodes 211 that are provided to the surface of the piezoelectric element 201; a power amplifier 203 that causes the piezoelectric element 201 to generate sonic waves by applying a voltage to each of the split electrodes 211; and a host computer and impedance measuring circuit that measure the electrical impedance spectrum of each split electrode 211 by applying a voltage to each of the split electrodes 211.

A method for monitoring the condition of a coil, wherein the coil is part of a device for determining at least one process variable of a medium in a container, includes applying an electrical excitation signal to the coil and receiving an electrical reception signal from the coil, determining a first value for the reception signal at a first predefinable measurement time, comparing the first value for the reception signal at the first measurement time with a reference value, and determining a condition indicator for the coil on the basis of the comparison. Disclosed also is a device that is designed for carrying out the disclosed method.

A monitoring apparatus is disclosed that includes a.) at least one acoustic pickup, b.) a sound pressure sensor acoustically coupled to the at least one acoustic pickup, and c.) a computing device interfaced to the sound pressure sensor. The at least one acoustic pickup may be submerged in or located in proximity to flowing fluid. The sound sensor is configured to acquire sound intensity waveforms naturally generated by the flowing fluid as a source of data patterns for training the apparatus as well stimuli used to generate responses about flow conditions. The computing device is configured to quantify flow parameters of the flowing fluid from sound utterances and visual appearances intrinsically expressed by the flow using machine learning models.

The current invention relates to methods and systems for evaluating a filling state of a load bearing means by means of a monitoring system comprising a sensing module; said load bearing means adapted for being carried by a transport unit; said load bearing means comprising a loading space; said sensing module situated in proximity to said load bearing means and outside of said loading space; said sensing module comprising an emitter, a receiver, an evaluator and a memory comprising calibration data; said sensing module configured for carrying out a plurality of steps; wherein a spacing S between said emitter and said receiver does not exceed 200 mm; and wherein a maximum dimension M of said load bearing means is not smaller than 4 m.

In an embodiment an ultrasonic transducer includes an ultrasonic unit with a housing in which a piezoelectric element is located, wherein the ultrasonic unit includes at least one electrical connecting lead leading out of the housing, the connecting lead being configured for connection to control and/or evaluation electronics arranged separately from the ultrasonic unit, and wherein the ultrasonic unit is configured to operate in a thickness oscillation mode.

A method (100) for estimating a volume of fuel available in a fuel tank (6) of a transport vehicle (1), the tank (6) comprising a tank wall inside which a space is defined for containing fuel, the method (100) comprising, in sequence, the steps of: a) exciting (101) a vibration of the tank (6); b) acquiring (102) a response signal correlated to a frequency response produced by the tank (6) due the excited vibration; c) processing (103) the acquired response signal to obtain an estimate of the initial volume of fuel available in the tank (6); d) gradually taking (104) fuel from the tank (6) with the transport vehicle (1) in use; e) estimating (105) a quantity of fuel taken gradually from the tank (6); f) estimating (106) the volume of fuel available in the tank (6) based on the initial volume and quantity estimate of fuel taken gradually.

A system and method for determining when a sand separator should be purged to remove solids from the sand separator. The system can include an acoustic sensor which detects the frequency of audible sound coming from the inner chamber of the vessel and generate a signature signal representative of the frequency of audible sound. There is a processor connected to the acoustic sensor and configured to compare the signature signal with a set frequency range of audible sound which in turn generates a signal indicating when the signature frequency and the set frequency are in overlapping relationship.

The present disclosure relates to a method for determining at least one process variable of a medium. The method includes steps of recording a first value for the process variable by means of a first method for determining the process variable and recording a second value for the process variable by means of a second method for determining the process variable. The method also includes steps of selecting at least one of the detected values for the process variable by means of a classifier and outputting the selected value for the process variable. The present disclosure further relates to a computer program designed for executing a method according to the present disclosure, and to a computer program product having a computer program according to the present disclosure.

Vibration sensor comprising a membrane, which can be excited to vibrate by means of a drive, wherein the drive has at least one piezo actuator, which is designed so as to be bonded with the membrane, wherein the membrane has at least one centering device that is designed to be suitable for orienting and keeping the drive centered relative to the membrane.